Display device and method of manufacturing the same

ABSTRACT

According to one embodiment, a method of manufacturing a display device, includes preparing a first substrate formed such that a first resin layer is formed on a first support substrate, preparing a second substrate formed such that a second resin layer is formed on a second support substrate, attaching the first substrate and the second substrate, peeling the second support substrate from the second resin layer by radiating a first laser beam toward the second substrate, mounting a signal supply source on a first mounting portion in a state in which the second resin layer, which is opposed to the first mounting portion, is warped in a direction away from the first mounting portion, and adhering the first resin layer and the second resin layer.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based upon and claims the benefit of priority fromJapanese Patent Application No. 2013-116178, filed May 31, 2013, theentire contents of which are incorporated herein by reference.

FIELD

Embodiments described herein relate generally to a display device and amethod of manufacturing the display device.

BACKGROUND

Flat-panel display devices, such as an organic electroluminescence (EL)display device and a liquid crystal display device, have been used invarious fields. In recent years, as regards mobile information terminaldevices such as mobile phones and PDAs (personal digital assistants),there has been an increasing demand for a display device having a lessthickness and a less weight.

For example, such a technique has been proposed that peeling of aconnection part is suppressed by providing a wiring board between aflexible first substrate and a flexible second substrate on the outsideof a display portion. In addition, as another example, such a techniquehas been proposed that a flexible display panel module is sandwichedbetween two resin sheets, these two resin sheets arethermocompression-bonded, and a flexible printed circuit board, which isconnected to an end portion of the display panel module, is alsosandwiched between the two resin sheets, thereby enhancing sealingproperties and ensuring protection against the external environment.

On the other hand, there has been a demand for simplifying amanufacturing process and improving productivity in achievingmass-production of display devices, while enhancing reliability.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a view which schematically illustrates a cross-sectionalstructure of a display device 1 according to an embodiment.

FIG. 1B is a plan view which schematically illustrates the displaydevice 1 shown in FIG. 1A.

FIG. 1C is a view which schematically illustrates a cross-sectionalstructure including a display element portion 120 of the display device1 of the embodiment.

FIG. 1D is a view which schematically illustrates a cross-sectionalstructure including a mounting portion 130 of the display device 1 ofthe embodiment.

FIG. 2 is a view for describing a method of manufacturing the displaydevice 1 of the embodiment, FIG. 2 illustrating a step of preparing afirst mother substrate M1.

FIG. 3 is a view for describing the method of manufacturing the displaydevice 1 of the embodiment, FIG. 3 illustrating a step of preparing asecond mother substrate M2.

FIG. 4 is a schematic plan view of the second mother substrate M2 shownin FIG. 3.

FIG. 5 is a view for describing the method of manufacturing the displaydevice 1 of the embodiment, FIG. 5 illustrating a step of attaching thefirst mother substrate M1 and the second mother substrate M2.

FIG. 6 is a view for describing the method of manufacturing the displaydevice 1 of the embodiment, FIG. 6 illustrating a step of peeling asecond support substrate 200 of the second mother substrate M2.

FIG. 7 is a view for describing the method of manufacturing the displaydevice 1 of the embodiment, FIG. 7 illustrating a step of cutting afirst resin layer 110 and a second resin layer 210.

FIG. 8 is a view for describing the method of manufacturing the displaydevice 1 of the embodiment, FIG. 8 illustrating a step of mounting asignal supply source.

FIG. 9 is a view for describing the method of manufacturing the displaydevice 1 of the embodiment, FIG. 9 illustrating a step of attaching thefirst resin layer 110 and second resin layer 210, with the signal supplysource being interposed.

FIG. 10 is a view for describing the method of manufacturing the displaydevice 1 of the embodiment, FIG. 10 illustrating a step of peeling afirst support substrate 100 of the first mother substrate M1.

FIG. 11 is a view for describing another method of manufacturing thedisplay device 1 of the embodiment, FIG. 11 illustrating a step ofmounting a signal supply source.

FIG. 12 is a view which schematically illustrates anothercross-sectional structure including the display element portion 120 ofthe display device 1 of the embodiment.

FIG. 13 is a view which schematically illustrates anothercross-sectional structure including the display element portion 120 ofthe display device 1 of the embodiment.

FIG. 14 is a view for describing a method of manufacturing the displaydevice 1 of the embodiment, FIG. 14 illustrating another step ofpreparing the first mother substrate M1.

DETAILED DESCRIPTION

In general, according to one embodiment, a method of manufacturing adisplay device, includes: preparing a first substrate formed such that afirst resin layer is formed on a first support substrate, and thereaftera first display element portion and a first mounting portion are formedin a first region above the first resin layer and a second displayelement portion and a second mounting portion are formed in a secondregion which neighbors the first region; preparing a second substrateformed such that a second resin layer is formed on a second supportsubstrate; attaching the first substrate and the second substrate;peeling the second support substrate from the second resin layer byradiating a first laser beam toward the second substrate; cutting thefirst resin layer and the second resin layer by radiating a second laserbeam, which is different in wavelength from the first laser beam, towardthe first resin layer and the second resin layer; mounting a signalsupply source on the first mounting portion in a state in which thesecond resin layer, which is opposed to the first mounting portion, iswarped in a direction away from the first mounting portion; and adheringthe first resin layer and the second resin layer in a state in which thesignal supply source is held between the first resin layer and thesecond resin layer.

According to another embodiment, a display device includes: an arraysubstrate including a first resin substrate, and a display elementportion and a mounting portion formed above the first resin substrate; acounter-substrate including a second resin substrate which is formed inthe same shape as the first resin substrate and is opposed to thedisplay element portion and the mounting portion; a first adhesive whichadheres the display element portion of the array substrate and thecounter-substrate; a signal supply source mounted on the mountingportion; and a second adhesive which adheres the first resin substrateand the second resin substrate in a state in which the signal supplysource is held between the first resin substrate and the second resinsubstrate.

Embodiments will now be described in detail with reference to theaccompanying drawings. In the drawings, structural elements having thesame or similar functions are denoted by like reference numerals, and anoverlapping description is omitted.

FIG. 1A is a view which schematically illustrates a cross-sectionalstructure of a display device 1 according to the embodiment. Adescription is given of a cross-sectional structure of an organic ELdisplay device as an example of a sheet-shaped display device 1.

Specifically, the display device 1 includes an array substrate AR and acounter-substrate CT. The array substrate AR is formed by using a firstresin substrate 10. The array substrate AR includes a display elementportion 120 and a mounting portion 130, on on inner surface of the firstresin substrate 10, that is, on the side thereof facing thecounter-substrate CT. The display element portion 120 includes aplurality of organic EL elements OLED. Each organic EL element OLEDemits, for example, white light.

Signal supply sources, such as an IC chip 2 and a flexible printedcircuit board 3, which supply necessary signals for driving the organicEL elements OLED, are mounted on the mounting portion 130.

The counter-substrate CT is formed by using a transparent second resinsubstrate 30. The second resin substrate 30 is opposed to the displayelement portion 120 and mounting portion 130. The counter-substrate CTincludes a color filter layer 220 on an inner surface of the secondresin substrate 30, that is, on the side thereof facing the arraysubstrate AR. The color filter layer 220 is composed of a plurality ofkinds of color filters with different colors. The color filter layer 220is opposed to the display element portion 120, and the color filters ofthe respective colors are opposed to the organic EL elements OLED.

The array substrate AR and counter-substrate CT are attached by anadhesive 41 and an adhesive 42. The adhesive 41 attaches the displayelement portion 120 and the counter-substrate CT. In an example, theadhesive 41 attaches the display element portion 120 and the colorfilter layer 220. In addition, the adhesive 41 also extends to theperiphery of the display element portion 120, and attaches the firstresin substrate 10 and second resin substrate 30. The adhesive 42attaches the first resin substrate 10 and second resin substrate 30 inthe state in which the signal supply sources (IC chip 2 and flexibleprinted circuit board 3) are held between the first resin substrate 10and second resin substrate 30. Each of the adhesive 41 and adhesive 42is formed of a material with low moisture permeability, and functions asa moisture barrier film or a sealing film.

FIG. 1B is a plan view which schematically illustrates the displaydevice 1 shown in FIG. 1A.

The array substrate AR and counter-substrate CT have the same outershape, and have end portions overlapping each other. Specifically, thefirst resin substrate 10 and second resin substrate 30 are formed in thesame shape, and the end portions of the first resin substrate 10 and theend portions of the second resin substrate 30 overlap with each other onthe four sides. Although the depiction of the organic EL elements, etc.is omitted, the display element portion 120 is formed in a rectangularshape, and the color filter layer 220 is disposed in a manner to overlapthe display element portion 120. The adhesive 41 is disposed not onlybetween the display element portion 120 and the color filter layer 220,but is also disposed in a manner to surround the display element portion120 and the color filter layer 220. In the mounting portion 130, theadhesive 42 is disposed in a manner to cover the area on which the ICchip 2 and flexible printed circuit board 3 are mounted.

FIG. 1C is a view which schematically illustrates a cross-sectionalstructure including the display element portion 120 of the displaydevice 1 of the embodiment. A description is given of a cross-sectionalstructure of the display device 1 of a top emission type.

Specifically, the array substrate AR includes switching elements SW1 toSW3 and organic EL elements OLED1 to OLED3 on an inner surface 10A sideof the first resin substrate 10. The inner surface 10A of the firstresin substrate 10 is covered with a first insulation film 11. The firstinsulation film 11 functions as an inner surface barrier film forsuppressing entrance of ionic impurities from the first resin substrate10 or entrance of moisture via the first resin substrate 10. The firstinsulation film 11 is formed of an inorganic material such as siliconnitride (SiN), silicon oxide (SiO) or silicon oxynitride (SiON), and iscomposed of a single layer or a multilayer. Incidentally, when anotherinsulation film, which is located on the inner surface 10A side of thefirst resin substrate 10, functions as a barrier film, the firstinsulation film 11 may be omitted.

The switching elements SW1 to SW3 are formed on the first insulationfilm 11. These switching elements SW1 to SW3 are, for example, thin-filmtransistors (TFTs) each including a semiconductor layer SC. Theswitching elements SW1 to SW3 have the same structure. In thedescription below, attention is paid to the switching element SW1, andthe structure thereof is described more specifically.

In the example illustrated, the switching element SW1 is of a top gatetype, but may be of a bottom gate type. The semiconductor layer SC isformed of, for example, amorphous silicon, polysilicon, or an oxidesemiconductor. The semiconductor layer SC is formed on the firstinsulation film 11, and is covered with a second insulation film 12. Thesecond insulation film 12 is also disposed on the first insulation film11. A gate electrode WG of the switching element SW1 is formed on thesecond insulation film 12. The gate electrode WG is covered with a thirdinsulation film 13. The third insulation film 13 is also disposed on thesecond insulation film 12. A source electrode WS and a drain electrodeWD of the switching element SW1 are formed on the third insulation film13. The source electrode WS and drain electrode WD are put in contactwith the semiconductor layer SC. The source electrode WS and drainelectrode WD are covered with a fourth insulation film 14. The fourthinsulation film 14 is also disposed on the third insulation film 13.

The organic EL elements OLED1 to OLED3 are formed on the fourthinsulation film 14. In the example illustrated, the organic EL elementOLED1 is electrically connected to the switching element SW1, theorganic EL element OLED2 is electrically connected to the switchingelement SW2, and the organic EL element OLED3 is electrically connectedto the switching element SW3. Each of the organic EL elements OLED1 toOLED3 is configured as a top emission type which emits white lighttoward the counter-substrate CT. The organic EL elements OLED1 to OLED3have the same structure.

The organic EL element OLED1 includes an anode PE1 which is formed onthe fourth insulation film 14. The anode PE1 is in contact with thedrain electrode WD of the switching element SW1 and is electricallyconnected to the switching element SW1. Similarly, the organic ELelement OLED2 includes an anode PE2 which is electrically connected tothe switching element SW2, and the organic EL element OLED3 includes ananode PE3 which is electrically connected to the switching element SW3.

The organic EL elements OLED1 to OLED3 further include an organic lightemission layer ORG and a cathode CE. The organic light emission layerORG is located on the anodes PE1 to PE3. For example, the organic lightemission layer ORG is continuously formed, without a break, over theorganic EL elements OLED1 to OLED3. The cathode CE is located on theorganic light emission layer ORG. The cathode CE is continuously formed,without a break, over the organic EL elements OLED1 to OLED3.

Specifically, the organic EL element OLED1 is composed of the anode PE1,organic light emission layer ORG and cathode CE. Similarly, the organicEL element OLED2 is composed of the anode PE2, organic light emissionlayer ORG and cathode CE, and the organic EL element OLED3 is composedof the anode PE3, organic light emission layer ORG and cathode CE.

In the meantime, in the organic EL elements OLED1 to OLED3, a holeinjection layer or a hole transport layer may be further providedbetween each of the anodes PE1 to PE3 and the organic light emissionlayer ORG, and an electron injection layer or an electron transportlayer may be further provided between the organic light emission layerORG and the cathode CE.

In the example illustrated, the organic EL elements OLED1 to OLED3 arepartitioned by ribs 15. The ribs 15 are formed on the fourth insulationfilm 14 and cover the edges of the anodes PE1 to PE3. Although notdescribed in detail, the ribs 15 are formed, for example, in a gridshape or in a stripe shape on the fourth insulation film 14.

Although not illustrated, it is desirable that the organic EL elementsOLED1 to OLED3 be sealed by a transparent sealing film. As the sealingfilm, a single layer or a multilayer of a transparent inorganic material(e.g. silicon nitride, silicon oxide) is applicable, and also amultilayer, which is formed by alternately stacking a thin film of aninorganic material and a thin film of an organic material, isapplicable.

The display element portion 120 corresponds to a structure body of aregion in which plural organic EL elements OLED are arranged, and issubstantially a structure body of a display area which displays animage.

The counter-substrate CT includes a color filter layer 220 and a barrierlayer 31 on an inner surface 30A side of the second resin substrate 30.

In the present embodiment, the first resin substrate 10 and second resinsubstrate 30 are formed of, for example, a material consisting mainly ofpolyimide (PI). Each of the first resin substrate 10 and second resinsubstrate 30 has a thickness of, e.g. 5 to 30 μm. It is desirable touse, aside from polyimide, a resin material with high heat resistance,such as polyamide imide or polyaramide, as the material of the firstresin substrate 10 and second resin substrate 30. In particular, sincelight emitted from the top-emission type organic EL elements OLED1 toOLED3 passes through the second resin substrate 30, it is desirable thatthe second resin substrate 30 be formed of a material with hightransparency, and be formed of polyimide among the above-mentionedmaterials.

In the case where one display pixel is composed of sub-pixels of threecolors of red, blue and green, the color filter layer 220 includes acolor filter CF1, a color filter CF2 and a color filter CF3. The colorfilter CF1 is a blue color filter which is opposed to the organic ELelement OLED1 and passes a light component of a blue wavelength of whitelight. The color filter CF2 is a green color filter which is opposed tothe organic EL element OLED2 and passes a light component of a greenwavelength of white light. The color filter CF3 is a red color filterwhich is opposed to the organic EL element OLED3 and passes a lightcomponent of a red wavelength of white light. In the meantime, in thecase where one display pixel is composed of sub-pixels of four colors ofred, blue, green and white, the color filter layer 220 includes atransparent color filter which is opposed to an organic EL element OLED,in addition to the blue color filter, green color filter and red colorfilter.

The barrier layer 31 covers the color filter layer 220. As the barrierlayer 31, a single layer or a multilayer of a transparent inorganicmaterial (e.g. silicon nitride, silicon oxide) is applicable, and also amultilayer, which is formed by alternately stacking a thin film of aninorganic material and a thin film of an organic material, isapplicable. Incidentally, the barrier layer 31 may be disposed betweenthe second resin substrate 30 and the color filter layer 220.

The display element portion 120 of the array substrate AR andcounter-substrate CT are attached by the transparent adhesive 41.

In the display device 1, when each of the organic EL elements OLED1 toOLED3 has emitted light, this radiated light (white light) is emitted tothe outside via the color filter CF1, color filter CF2 or color filterCF3. At this time, a light component of a blue wavelength of the whitelight, which has been radiated from the organic EL element OLED1, passesthrough the color filter CF1. In addition, a light component of a greenwavelength of the white light, which has been radiated from the organicEL element OLED2, passes through the color filter CF2. A light componentof a red wavelength of the white light, which has been radiated from theorganic EL element OLED3, passes through the color filter CF3. Thereby,color display is realized.

FIG. 1D is a view which schematically illustrates a cross-sectionalstructure including the mounting portion 130 of the display device 1 ofthe embodiment.

In the example illustrated, in the mounting portion 130 of the arraysubstrate AR, the first insulation film 11, second insulation film 12,third insulation film 13 and fourth insulation film 14 are stacked onthe first resin substrate 10. In the mounting portion 130, a pad portionEA, on which the IC chip 2 is mounted, and a pad portion EB, on whichthe flexible printed circuit board 3 is mounted, are provided on thefourth insulation film 14. The pad portion EB is located closer to theend portion side of the array substrate AR than the pad portion EA.

Incidentally, although not illustrated, in the mounting portion 130,various wirings and various circuits, which are formed in the same layeras the gate electrodes, source electrodes and anodes, are formed. Thepad portion EA and pad portion EB are electrically connected to thesevarious wirings and circuits.

In the counter-substrate CT, the inner surface 30A of the second resinsubstrate 30 is covered with the barrier layer 31. As will be describedlater, the barrier layer 31 is a film with a compressive stress.Incidentally, it should suffice if this barrier layer 31 is disposed tobe opposed to at least the mounting portion 130.

The counter-substrate CT is attached to the mounting portion 130 of thearray substrate AR by the adhesive 42.

Next, a description is given of an example of a method of manufacturingthe display device 1 according to the embodiment.

To begin with, as illustrated in FIG. 2, a first mother substrate M1 isprepared. Specifically, a film of a polyimide precursor compound with athickness of 5 to 30 μm is formed on a first support substrate 100 whichis formed of no-alkali glass or the like, by using a film-forming devicesuch as a slit coater. Then, this film is cured by heating, and a firstresin layer 110 is formed. As an example, the thickness of the firstresin layer 110 was set at 10 μm. The first resin layer 110 correspondsto the above-described first resin substrate 10. The first resin layer110 continuously extends, without a break, over the first supportsubstrate 100.

Then, on the first resin layer 110, a first display element portion 121and a first mounting portion 131 are formed in a first region A1, asecond display element portion 122 and a second mounting portion 132 areformed in a second region A2 which neighbors the first region A1, and athird display element portion 123 and a third mounting portion 133 areformed in a third region A3 which neighbors the second region A2.

The first display element portion 121, second display element portion122 and third display element portion 123 have the same structure andcorrespond to the above-described display element portion 120. Althougha detailed structure is not illustrated, each of the first displayelement portion 121, second display element portion 122 and thirddisplay element portion 123 includes a plurality of switching elementsSW and a plurality of organic EL elements OLED, which are arranged in amatrix. In addition, the first mounting portion 131, second mountingportion 132 and third mounting portion 133 have the same structure andcorrespond to the above-described mounting portion 130. Although adetailed structure is not illustrated, each of the first mountingportion 131, second mounting portion 132 and third mounting portion 133includes a pad portion EA and a pad portion EB.

Subsequently, as illustrated in FIG. 3, a second mother substrate M2 isprepared. Specifically, a transparent second resin layer 210 is formedon an inner surface 200A of a second support substrate 200 which isformed of no-alkali glass or the like. The method of forming the secondresin layer 210 is the same as that of the first resin layer 110, and adescription thereof is omitted. As an example, the thickness of thesecond resin layer 210 was set at 10 μm. The second resin layer 210corresponds to the above-described second resin substrate 30. The secondresin layer 210 continuously extends, without a break, over the innersurface 200A of the second support substrate 200.

Then, a first color filter layer 221, a second color filter layer 222and a third color filter layer 223 are formed on the second resin layer210. The first color filter layer 221 is formed at such a position as toface the first display element portion 121, when the first mothersubstrate M1 and second mother substrate M2 are attached. Similarly, thesecond color filter layer 222 is formed at such a position as to facethe second display element portion 122, and the third color filter layer223 is formed at such a position as to face the third display elementportion 123. The first color filter layer 221, second color filter layer222 and third color filter layer 223 have the same structure, and eachof the first color filter layer 221, second color filter layer 222 andthird color filter layer 223 includes a first color filter (blue colorfilter) CF1, a second color filter (green color filter) CF2 and a thirdcolor filter (red color filter) CF3.

Subsequently, a barrier layer 31, which covers the first color filterlayer 221, second color filter layer 222 and third color filter layer223, is formed. When this barrier layer 31 is formed, the barrier layer31 is formed under such a condition that the barrier layer 31 has acompressive stress. The barrier layer 31 continuously extends without abreak, and also extends over the second resin layer 210.

An adhesive 41 is coated on those parts of the surface of the barrierlayer 31, which overlap the first color filter layer 221, second colorfilter layer 222 and third color filter layer 223.

As illustrated in FIG. 4, each of the first color filter CF1, secondcolor filter CF2 and third color filter CF3 is formed in a stripe shape,and the first color filter CF1, second color filter CF2 and third colorfilter CF3 are cyclically arranged in the named order.

Subsequently, as illustrated in FIG. 5, the first mother substrate M1and second mother substrate M2 are attached. Specifically, the firstdisplay element portion 121 and first color filter layer 221 areattached by the adhesive 41 via the barrier layer 31, the second displayelement portion 122 and second color filter layer 222 are attached bythe adhesive 41 via the barrier layer 31, and the third display elementportion 123 and third color filter layer 223 are attached by theadhesive 40 via the barrier layer 31.

Following the above, as illustrated in FIG. 6, as regards the secondmother substrate M2, the second support substrate 200 is peeled from thesecond resin layer 210, and the second support substrate 200 is removed.Specifically, as regards the second mother substrate M2, a laser beam isradiated on almost the entire surface of the second support substrate200 from an outer surface 200B side of the second support substrate 200,and ablation is performed. At this time, as the light source of thelaser beam that is radiated, use can be made of a light source (laserdevice) or a heat source (electromagnetic wave radiation device) whichexhibits local energy absorption at an interface between the secondsupport substrate 200 and the second resin layer 210. In this example,an excimer laser device was used. In an example, the oscillationwavelength of the excimer laser device is, e.g. 308 nm.

By the radiation of the laser beam, the laser beam is properly absorbedin the second resin layer 210, and the absorbed laser beam changes tothermal energy, and a part of the second resin layer 210 is evaporatedin the vicinity of the interface between the second resin layer 210 andthe second support substrate 200. Thus, the second support substrate 200and the second resin layer 210 are separated. Thereby, the second resinlayer 210, barrier layer 31, first color filter layer 221, second colorfilter layer 222 and third color filter layer 223 are transferred ontothe first mother substrate M1. This method is called “laser ablation”,etc.

Then, as illustrated in FIG. 7, the first resin layer 110 and secondresin layer 210 are cut. Specifically, a laser beam is radiated from thesecond resin layer 210 side, and the first resin layer 110 and secondresin layer 210 are cut at the same time in the first region A1, secondregion A2 and third region A3. At this time, as the light source of thelaser beam that is radiated, a light source having a wavelength, whichis different from the wavelength of the light source used for laserablation, is applied. In particular, it is important to avoid as much aspossible the occurrence of microcracks in various thin films andelectrode layers which are stacked on the first resin layer 110 andsecond resin layer 210, and it is desirable to use, for instance, ahigh-energy picosecond laser device with a very narrow pulse width. Forexample, as the light source, a third-harmonic generation (THG) laserdevice is applicable. The oscillation wavelength of the third-harmonicgeneration laser device was, e.g. 355 nm, and the frequency was 100 MHz.

By the radiation of the laser beam, the first resin layer 110 and secondresin layer 210 are cut in the same shape in the first region A1, secondregion A2 and third region A3.

Thereafter, the first support substrate 100 is cut by scribing along cutlines indicated by broken lines. Thereby, chips C1 to C3, which areseparated from the first mother substrate M1, are obtained. The chip C1obtained from the first region A1 includes the first display elementportion 121 and first mounting portion 131. The chip C2 obtained fromthe second region A2 includes the second display element portion 122 andsecond mounting portion 132. The chip C3 obtained from the third regionA3 includes the third display element portion 123 and third mountingportion 133.

Subsequently, as illustrated in FIG. 8, as regards the separated chipC1, the IC chip 2 and flexible printed circuit board 3, which are signalsupply sources, are mounted on the first mounting portion 131. At thistime, the second resin layer 210, which is opposed to the first mountingportion 131, is warped in a direction away from the first mountingportion 131. The reason for this is that since the barrier layer 31,which is formed on the first mounting portion 131 side of the secondresin layer 210, is formed to have a compressive stress at a time offilm formation, the compressive stress of the barrier layer 31 isreleased when the barrier layer 31 is cut together with the second resinlayer 210, and such an internal stress as to expand acts. Then, in thestate in which the second resin layer 210 is warped, the IC chip 2 andflexible printed circuit board 3 are mounted on the first mountingportion 131. Since the first support substrate 100 is left as anunderlayer of the first resin layer 110, it is possible to secure asufficient support strength of the first mounting portion 131, against apressing force which is applied at the time of mounting the IC chip 2and flexible printed circuit board 3. Although not illustrated, signalsupply sources are also mounted on the second mounting portion 132 ofthe chip C2 and the third mounting portion 133 of the chip C3.

Following the above, as illustrated in FIG. 9, in the first mountingportion 131, the first resin layer 110 and second resin layer 210 areattached by an adhesive 42. Thereby, the IC chip 2 and flexible printedcircuit board 3, which are mounted on the first mounting portion 131,are held between the first resin layer 110 and second resin layer 210.Although not illustrated, as regards the second mounting portion 132 ofthe chip C2, the first resin layer 110 and second resin layer 210 areattached by the adhesive 42, and the signal supply sources are heldtherebetween. Similarly, as regards the third mounting portion 133 ofthe chip C3, the first resin layer 110 and second resin layer 210 areattached by the adhesive 42, and the signal supply sources are heldtherebetween.

Subsequently, as illustrated in FIG. 10, as regards the chip 1, thefirst support substrate 100 is peeled from the first resin layer 110,and the first support substrate 100 is removed. Although not describedin detail, like the laser ablation illustrated in FIG. 6, a laser beamis radiated on the first resin layer 110 from the outer surface side ofthe first support substrate 100, thereby separating the first supportsubstrate 100 and the first resin layer 110. At this time, an excimerlaser device was used as the light source, like the case described withreference to FIG. 6. Although not illustrated, by similar laserablation, the first support substrate 100 and the first resin layer 110are separated as regards the chip C2, and the first support substrate100 and the first resin layer 110 are separated as regards the chip C3.

Thereby, the display device 1 of the embodiment is manufactured.

According to the above-described embodiment, the first mother substrateM1, on which the display element portions and mounting portions areformed after the first resin layer 110 is formed on the first supportsubstrate 100, and the second mother substrate M2, on which the colorfilter layers and barrier layer are formed after the second resin layer210 is formed on the second support substrate 200, are attached.Thereafter, by the radiation of a laser beam, the second supportsubstrate 200 is peeled from the second resin layer 210. Further, by theradiation of a laser beam, the first resin layer 110 and second resinlayer 210 are cut batchwise. The first resin layer 110 and second resinlayer 210 are formed in the same shape, and become the first resinsubstrate 10 and second resin substrate 30 of the organic EL displaydevice that is the final product. Then, since that region of the secondresin layer 210, which is opposed to the mounting portion, is notadhered, this region warps by its own internal stress and exposes themounting portion. Thus, the mounting of signal supply sources on themounting portion is made easier. Therefore, the productivity can beimproved in mass-producing display devices.

According to the study by the inventor, it was confirmed that the secondresin layer 210 warps with proper naturalness immediately after thesecond resin layer 210 is cut, by setting the thickness of the secondresin layer 210 at 30 μm or less, preferably about 10 μm, and bydisposing the barrier layer on that inner surface of the second resinlayer 210, which is opposed to the mounting portion.

In addition, according to the present embodiment, after the signalsupply sources are mounted, the second resin layer 210, which is opposedto the mounting portion, is attached to the first resin layer 110. Thus,the signal supply sources are held between the first resin layer 110 andsecond resin layer 210. Therefore, separation of the signal supplysources from the mounting portion can be suppressed, and the strength ofmounting can be improved. In addition, in the mounting portion, sincethe adhesive, which attaches the first resin layer 110 and second resinlayer 210, has low moisture permeability, the entrance of moisture viathe adhesive can be suppressed, and the damage to the signal supplysources due to moisture can be reduced. Therefore, the reliability canbe enhanced.

Furthermore, according to the embodiment, in the second motherboard M2,the second resin layer 210 extends over the entirety of the innersurface 200A of the second support substrate 200. Thus, the laser beam,which is radiated on the second mother substrate M2 when the secondsupport substrate 200 is to be peeled from the second resin layer 210,is properly absorbed by the second resin layer 210 and the second resinlayer 210 is separated from the second support substrate 200, while thelaser beam traveling toward the first mother substrate M1 is blocked orabsorbed by the second resin layer 210. Thereby, it is possible tosuppress the damage by the laser beam to the first mother substrate M1,in particular, the mounting portion.

Besides, according to the embodiment, since the display device 1 isconfigured such that the first resin substrate 10 and second resinsubstrate 30 are applied, compared to a display device in which glasssubstrates are applied, the thickness and weight can be reduced,flexibility is high, and the degree of freedom in shaping is high. Inaddition, since each of the first resin substrate 10 and second resinsubstrate 30 has a moisture barrier layer on the inner surface thereof,the entrance of moisture via the first resin substrate 10 and secondresin substrate 30 can be suppressed. Thus, the damage due to moistureto the organic EL elements OLED1 to OLED3 can be reduced. Therefore,degradation in display quality due to occurrence of dark spots can besuppressed.

Next, another method of manufacturing the display device 1 in theembodiment is briefly described. A description overlapping with theabove-described manufacturing method is omitted.

The manufacturing method to be described below differs from themanufacturing method described with reference to FIG. 8 in that thesecond resin layer 210, which is opposed to the first mounting portion131, is warped by electrostatic attraction.

Specifically, as illustrated in FIG. 11, an electrostatic attractionhead 400 is disposed above the second resin layer 210 which is opposedto the first mounting portion 131 of the separated chip C1. When the ICchip 2 and flexible printed circuit board 3, which are signal supplysources, are mounted on the first mounting portion 131, the second resinlayer 210 is attracted and raised by electrostatic attraction by theelectrostatic attraction head 400. Specifically, the second resin layer210 is raised in a direction away from the first mounting portion 131.Thereby, the second resin layer 210 is warped in the direction away fromthe first mounting portion 131.

Then, in the state in which the second resin layer 210 is warped, the ICchip 2 and flexible printed circuit board 3 are mounted on the firstmounting portion 131. Thereafter, at the first mounting portion 131, thefirst resin layer 110 and second resin layer 210 are attached by theadhesive 42, as described with reference to FIG. 9, and the firstsupport substrate 100 is peeled from the first resin layer 110, asdescribed with reference to FIG. 10.

With this manufacturing method, the same advantageous effects as withthe above-described manufacturing method can be obtained.

In the above example, the description has been given of the displaydevice in which the counter-substrate CT includes the color filter layer220, and the manufacturing method of the the display device in which thecolor filter layer 220 is formed on the counter-substrate CT. However,the embodiment is not limited to this example. For instance, the arraysubstrate AR may include the color filter layer 220.

FIG. 12 is a view which schematically illustrates anothercross-sectional structure including the display element portion 120 ofthe display device 1 of the embodiment.

The example illustrated relates to a bottom-emission-type display device1. Specifically, the display device 1 illustrated in FIG. 12 differsfrom the display device 1 described with reference to FIG. 1C in thatthe color filter layer 220 is disposed on the inner surface 10A of thefirst resin substrate 10, and that each of the organic EL elements OLED1to OLED3 is configured as a bottom emission type which emits white lighttoward the first resin substrate 10. The color filter layer 220 isdisposed between the first resin substrate 10 and the first insulationfilm 11. In the example illustrated, the color filter CF1 is locatedbetween the organic EL element OLED1 and the first resin substrate 10,the color filter CF2 is located between the organic EL element OLED2 andthe first resin substrate 10, and the color filter CF3 is locatedbetween the organic EL element OLED3 and the first resin substrate 10.

FIG. 13 is a view which schematically illustrates anothercross-sectional structure including the display element portion 120 ofthe display device 1 of the embodiment.

The display device 1 of the bottom emission type illustrated in FIG. 13differs from the display device 1 illustrated in FIG. 12 in that thecolor filter layer 220 is substituted for the fourth insulation film 14.The color filter layer 220 is disposed between the third insulation film13 and the organic EL elements OLED1 to OLED3. In the exampleillustrated, the color filter CF1 is located between the organic ELelement OLED1 and the third insulation film 13, the color filter CF2 islocated between the organic EL element OLED2 and the third insulationfilm 13, and the color filter CF3 is located between the organic ELelement OLED3 and the third insulation film 13. Incidentally, the colorfilter layer 220 may be substituted for an insulation film other thanthe fourth insulation film 14.

The method of manufacturing the above-described bottom-emission-typedisplay devices 1 is the same as in the above-described example, exceptfor the step of preparing the first mother substrate M1 illustrated inFIG. 2, and the step of preparing the second mother substrate M2illustrated in FIG. 3.

FIG. 14 is a view for describing a method of manufacturing the displaydevice 1 of the embodiment, FIG. 14 illustrating another step ofpreparing the first mother substrate M1.

Specifically, a first resin layer 110 is formed on a first supportsubstrate 100 which is formed of no-alkali glass or the like. Then, afirst color filter layer 221, a second color filter layer 222 and athird color filter layer 223 are formed on the first resin layer 110.Thereafter, a first display element portion 121 and a first mountingportion 131 are formed in the first region A1, a second display elementportion 122 and a second mounting portion 132 are formed in the secondregion A2, and a third display element portion 123 and a third mountingportion 133 are formed in the third region A3. At this time, the firstdisplay element portion 121 is formed at a position overlapping thefirst color filter layer 221, the second display element portion 122 isformed at a position overlapping the second color filter layer 222, andthird display element portion 123 is formed at a position overlappingthe third color filter layer 223.

On the other hand, in the step of preparing the second mother substrateM2, a transparent second resin layer 210 is formed on the inner surface200A of the second support substrate 200, and thereafter a barrier layer31 covering the second resin layer 210 is formed.

The subsequent fabrication steps are the same as those in theabove-described example, and a description thereof is omitted.

With this bottom-emission-type display device and the manufacturingmethod thereof, the same advantageous effects as with theabove-described example of the top emission type can be obtained.

As has been described above, according to the present embodiment, therecan be provided a display device which can improve the productivity andreliability, and a manufacturing method thereof.

In the meantime, in the above-described embodiment, as an example of thedisplay device, the organic EL display device has been described.However, another example of the display device may be a liquid crystaldisplay device. In this case, the display element portion is configuredto include a pixel electrode in place of the anode, which is connectedto a switching element, a common electrode in place of the cathode, anda liquid crystal layer including liquid crystal molecules in place ofthe organic light emission layer. Light, which passes through the liquidcrystal layer, is modulated by switching the liquid crystal molecules byan electric field between the pixel electrode and common electrode. Usemay be made of a method in which a closed-loop-shaped sealant is used inplace of the adhesive 41, and a liquid crystal material is dispensed inthe inside surrounded by the sealant before the first mother substrateM1 and second mother substrate M2 are attached. Incidentally, the colorfilter layer may be provided on the array substrate or may be providedon the counter-substrate.

In the embodiment, the above-described laser ablation technique isapplied to the peeling between the first support substrate 100 and thefirst resin layer 110, and the peeling between the second supportsubstrate 200 and the second resin layer 210. Alternatively, othertechniques, such as a thermal rapid anneal technique, are applicable.

While certain embodiments have been described, these embodiments havebeen presented by way of example only, and are not intended to limit thescope of the inventions. Indeed, the novel embodiments described hereinmay be embodied in a variety of other forms; furthermore, variousomissions, substitutions and changes in the form of the embodimentsdescribed herein may be made without departing from the spirit of theinventions. The accompanying claims and their equivalents are intendedto cover such forms or modifications as would fall within the scope andspirit of the inventions.

What is claimed is:
 1. A method of manufacturing a display device,comprising: preparing a first substrate formed such that a first resinlayer is formed on a first support substrate, and thereafter a firstdisplay element portion and a first mounting portion are formed in afirst region above the first resin layer and a second display elementportion and a second mounting portion are formed in a second regionwhich neighbors the first region; preparing a second substrate formedsuch that a second resin layer is formed on a second support substrate;attaching the first substrate and the second substrate; peeling thesecond support substrate from the second resin layer by radiating afirst laser beam toward the second substrate; cutting the first resinlayer and the second resin layer by radiating a second laser beam, whichis different in wavelength from the first laser beam, toward the firstresin layer and the second resin layer; mounting a signal supply sourceon the first mounting portion in a state in which the second resinlayer, which is opposed to the first mounting portion, is warped in adirection away from the first mounting portion; and adhering the firstresin layer and the second resin layer in a state in which the signalsupply source is held between the first resin layer and the second resinlayer.
 2. The method of claim 1, further comprising forming a firstcolor filter layer, which is opposed to the first display elementportion, and a second color filter layer, which is opposed to the seconddisplay element portion, above the first resin layer or above the secondresin layer, before attaching the first substrate and the secondsubstrate.
 3. The method of claim 1, wherein, in said preparing thesecond substrate, a barrier layer, which is formed to have a compressivestress, is formed on that side of the second resin layer, which isopposed to the first substrate.
 4. The method of claim 1, wherein, insaid mounting the signal supply source, the second resin layer, which isopposed to the first mounting portion, is warped by electrostaticattraction.
 5. The method of claim 1, further comprising, after saidmounting the signal supply source, radiating the first laser beam towardthe first substrate, thereby peeling the first support substrate fromthe first resin layer.
 6. A display device comprising: an arraysubstrate including a first resin substrate, and a display elementportion and a mounting portion formed above the first resin substrate; acounter-substrate including a second resin substrate which is formed inthe same shape as the first resin substrate and is opposed to thedisplay element portion and the mounting portion; a first adhesive whichadheres the display element portion of the array substrate and thecounter-substrate; a signal supply source mounted on the mountingportion; and a second adhesive which adheres the first resin substrateand the second resin substrate in a state in which the signal supplysource is held between the first resin substrate and the second resinsubstrate.
 7. The display device of claim 6, further comprising a colorfilter layer which is opposed to the display element portion, above thefirst resin substrate or above the second resin substrate.
 8. Thedisplay device of claim 6, wherein the counter-substrate furtherincludes a barrier layer which is formed on an inner surface side of thesecond resin substrate and is opposed to at least the mounting portion.9. The display device of claim 8, wherein the barrier layer is a filmwith a compressive stress.